Why am I unattractive to local mosquitos?

June 25, 2006 9:46 PM

Why don't Bay Area mosquitos bite me? Last year, in Desolation Wilderness (CA), the air was thick with mosquitos, and I was bitten liberally and painfully. This year, in my apartment in the Bay Area, the air is again thick with mosquitos and I am without noticeable bites. Why?

Is the Bay Area home to many mosquitos that don't bite humans?

Am I personally disgusting to local mosquitos?

Have I become desensitized to the particular flavour of poison that local mosquitos use?

Is there some spraying programme that means they grow up unable to bite?

Or have they just not reached the point in their life cycle where they suck me dry?

posted by beniamino to science & nature (18 comments total)

Mosquitos are pretty local, you may react to one species or population and have no reaction at all to another.
posted by fshgrl at 9:51 PM on June 25, 2006

Have you stopped eating meat in the past year? I (a vegetarian) never get bitten whereas the meat eaters walking next to me always do.
posted by dobbs at 10:05 PM on June 25, 2006

The reaction is along the same line of an allergy - to something that gets under your skin when the mosquito jams its proboscis into you. If you don't have an allergy to whatever it is, you won't show that you've been bitten.
posted by ikkyu2 at 10:07 PM on June 25, 2006

dobbs: Whoa, yes I (mostly) have. Interesting.

ikkyu2: It sounds like you're saying that every mosquito's "saliva" is different, and that I've just never developed a reacton to the local variety. If so, why does one develop a reaction to one set of proteins and not another?

Perhaps I'll trap one and encourage it to bite me so I can see if (a) it will bite and (b) I react.
posted by beniamino at 10:29 PM on June 25, 2006

Since they don't bite, are you certain they are mosquitoes?

I never see skeeters in Silicon Valley. Except for that one time in Palo Alto.
posted by Rash at 11:06 PM on June 25, 2006

I have no factual information to add, but when I went to Costa Rica with my ex she got bitten to high hell while I also had no noticable bites. Me: vegan. Her: not.
posted by beerbajay at 12:58 AM on June 26, 2006

For what it's worth, whenever my vegetarian friend and I are out together, SHE is the one who always gets bit and not me. So, I don't know if I put much stock in the whole vegetarian slant.
posted by bristolcat at 4:48 AM on June 26, 2006

What about population density? I've never been to Wilderness, CA, but I'd figure there's a lot less people there than around the bay. Perhaps the buggers just aren't as ravenous for food in plentiful places. As well, they have more of a buffet to choose from.
posted by Atreides at 5:57 AM on June 26, 2006

I am a mosquito magnet, as is my father and my brother (my mom isn't, neither is my boyfriend's family - grrrrrr). One thing we've found that works is avoiding bananas and making sure we are eating a lot of citrus. There is something that happens when we sweat after eating bananas that makes the mosquito attraction even worse, but the mosquitos are manageable if we eat more citrus. This is anecdotal based on something my dad was told by one of his doctors, but it does appear to work. If you've upped your citrus eating, that might be making a difference too?
posted by Cyrie at 7:45 AM on June 26, 2006 [1 favorite]

Getting bitten, in my experience, is an individual thing. When out with a group (two nights ago, in fact) I'm always the one who gets the most bites. No one else was getting bitten and I got at least ten. However, if my father is there, he gets at least twice as many as me, and has a much more serious reaction. My dad gets bitten through his clothes. I'll never forget this one time my dad was complaining about the bugs and I thought he should just pipe down and deal with it, and then he took off a button down dress shirt to reveal half-dollar sized welts covering his entire back.

So I think mosquitos prefer certain individuals, and probably this varies by population of mosquitos as well.
posted by palegirl at 7:51 AM on June 26, 2006

Mosquitos locate their prey (you) based on smell Clearly individuals have different very different smells and people smell differently based on what they have been eating.

Since mosquitos are local, I'm going to go out on a limb and guess that mosquitos vary in what smells are very attractive to them as well. What something like DEET does is to mask your smell so mosquitos can't "find" you.

Perhaps the desolation wilderness mosquitos have an easier time finding you than the bay area ones.
posted by zia at 8:03 AM on June 26, 2006

It sounds like you're saying that every mosquito's "saliva" is different, and that I've just never developed a reacton to the local variety.

Actually, I took great pains to avoid saying that, because I don't know it to be true.

If so, why does one develop a reaction to one set of proteins and not another?

No one knows this, at least not understanding it on a level that can be used to help individual people with their problems.
posted by ikkyu2 at 9:03 AM on June 26, 2006

I have no scientific answer but offer my anecdotal experience. I don't recall having been bitten in the period since becoming a vegetarian as a schoolchild until 3 weeks ago when I was in a malarial region for the first time. I've travelled in the UK and continental Europe and in North America and not been bitten. 3 weeks ago I went to Sri Lanka and used liberal amounts of DEET and got bitten a dozen times. Since returning to the UK my housemates have been bitten here but I haven't at all. You're not alone in being attractive to mosquitos in one area and not in another.
posted by boudicca at 9:49 AM on June 26, 2006

My anecdotal evidence is that I was a mosquito-magnet as a meat-eater and they haven't been interested since I went vegetarian.
posted by Zed_Lopez at 9:57 AM on June 26, 2006

I've been a vegeterian for about 18 years, and I get bitten a lot by mozzies here in Califonia, so I'm not sure about the vege thing. I react badly to the ones that do bite me: big, itchy blotches.

I suspect that different populations have different tastes...
posted by baggers at 10:10 AM on June 26, 2006

Mosquitos locate their prey (you) based on smell

Not really, mostly they are attracted to heat and CO2.

What something like DEET does is to mask your smell so mosquitos can't "find" you.

Nope, what DEET does is kill them on contact. It's nasty stuff.
posted by fshgrl at 10:44 AM on June 26, 2006

Not to derail, but:

DEET disrupts the ability of biting insects to detect the source of carbon dioxide—the gas naturally given off by our skin and in our breath— which is what attracts mosquitoes and other insects to us. Insects aren’t killed—they just can’t locate their prey for a period of hours.

from deet.com
posted by bitmage at 2:22 PM on June 26, 2006

Thanks for your answers, everyone. Seems like this is a bit of a mystery.

Rash, Atreides: They're definitely mosquitos and there are plenty of them.

baggers & other proponents of "you are disgusting to them": This definitely seems possible; searching around, there are species that don't even like humans (e.g. Anopheles stigmaticus mentioned here).

Dobbs and other vegetarians: I had a look on pubmed, and found, as zia said, that mosquitos are attracted to particular animal and avian odours, and so it's somewhat plausible that a change in diet could result in a change in odour, and thus a change in attractiveness.

ikkyu2: The reason why 'no immune reaction' is strange to me is because I've been exposed to the local mozzies for years, so I'd expect to react to them. Odd that I should go away from home, and find a population of mosquitos that I'm already sensitive to.
posted by beniamino at 7:14 PM on June 26, 2006